数字语音通信服务是ＣＳＣＷ应用系统的重要组成部分。本文首先分析了自然型语音通信所需遵循的规则，建议使用双令牌来控制发言权，并描述了一个基于双令牌的发言控制协议。在此基础上，我们给出了一个自然型多点语音讨论系统ＶｏｉｃｅＣｈａｔ的设计和实现方案，最后结合某段典型的对话情景给出了应用实例 Digital voice communication service is an important part of CSCW application system. This paper first analyzes the rules to be followed for natural-type voice communications. It is recommended to use double tokens to control the floor and to describe a double tokens-based floor control protocol. On this basis, we give a design and implementation of VoiceChat, a natural multi-point voice discussion system. Finally, we give an example of application with a typical dialogue scenario